Exhaust gas cleaning element

Abstract

An improved exhaust gas cleaning element comprising a ceramic honeycomb structure body having inner wall surfaces defining plural cells, each cell defining a passageway through which exhaust gas flows, characterized in that a multiplicity of arranged projections are provided over the entire wall surfaces of the cells in the structure body, the projections extending into the exhaust gas passageway, and the wall surfaces having a multiplicity of through-holes communicating with the adjoining cell.

What is claimed is: 
     
       1. A rigid ceramic element adapted for capturing and retaining carbon from the exhaust gas of a diesel engine, said element comprising a ceramic monolithic honeycomb structure having inner wall surfaces defining a plurality of cells extending throughout the length of said element, each cell having an open inlet end and an open outlet end defining therebetween a passageway through which said exhaust gas flows, and an irregular reticulate ceramic layer coated upon said inner wall surfaces defining each of said cells, said ceramic layer including a multiplicity of irregularly arranged projections extending into said exhaust gas passageway so as to disturb the exhaust gas flow therethrough to activate the interaction between the exhaust gas and said inner wall surfaces to enhance the capturing and retaining of carbon from the exhaust gas. 
     
     
       2. A rigid ceramic element adapted for capturing and retaining carbon from the exhaust gas of a diesel engine, said element comprising a ceramic monolithic honeycomb structure having inner wall surfaces defining a plurality of cells extending throughout the length of said element, each cell having an open inlet end and an open outlet end defining therebetween a passageway through which said exhaust gas flows, said inner wall surfaces further including a multiplicity of through-holes communicating said passageways of adjoining cells, each cell having an irregular, reticulate ceramic layer coated upon said inner wall surface, the ceramic layer including a multiplicity of irregularly arranged projections extending into said exhaust gas passageway so as to disturb the exhaust gas flow therethrough to activate the interaction between the exhaust gas and said inner wall surfaces to enhance the capturing and retaining of carbon from the exhaust gas. 
     
     
       3. The ceramic element of claim 1 or 2 wherein alternating ones of said cell open inlet ends and open outlet ends include closure means for closing said alternating ones and for directing the exhaust gas to pass from one cell to an adjacent cell or cells as said exhaust gas flows through the ceramic element. 
     
     
       4. A rigid ceramic element adapted for capturing and retaining carbon from the exhaust gas of a diesel engine, said element comprising a porous ceramic mass having a skeleton structure defining a randomly arranged plurality of tortuous communicating spaces opening to the outside for allowing flow of said exhaust gas therethrough, and an irregular, reticulate ceramic layer coated on said skeleton structure and including a multiplicity of irregularly arranged projections extending into said spaces so as to disturb the exhaust gas flow therethrough to activate the interaction between the exhaust gas and said skeleton structure to enhance the capturing and retaining of carbon from the exhaust gas.